This application claims priority from Japanese patent application of Tanase et al, filed Jun. 1, 2001, No2001-167266, the complete disclosure of which is hereby incorporated into the present application by this reference.
1. Field of the Invention
The present invention relates to a head protecting airbag device for expanding an airbag while extending it at the time of a rollover (e.g., a turnover or a side roll) or a side collision of a vehicle. The airbag of the head protecting airbag device is folded up and housed above the upper edge of a window inside of the vehicle. Moreover, the airbag expands while extending to cover the inner side of the window when it admits an inflating gas.
2. Description of Related Art
The airbag device of the prior art for covering the window on the inner side of a vehicle with an airbag expanded is disclosed in International Laid-Open No. WO98/19894. In this airbag device, a folded airbag is housed above the upper edge of a side window positioned on the side face of the vehicle. At a predetermined time, moreover, an inflating gas flows from an inflator into the airbag so that the airbag expanded covers the inner side of the side window.
Moreover, the airbag having completed its expansion is so tensed in the longitudinal direction of the vehicle that it may not be moved to the outside of the vehicle by the passenger.
However, the following problems have occurred when such airbag is employed in the head protecting airbag device which is activated when a rollover (e.g., a turnover or a side roll) of the vehicle is predicted.
During the rollover of the vehicle, more specifically, it is unavoidable that the upper half of the passenger is seriously rocked in the transverse directions as the vehicle turns. When the airbag is extended and expanded with the passenger""s head portion being extremely close to the side window, for example, the airbag may be arranged not between the head portion and the side window but closer to the center of the cabin than the head portion inside of the vehicle. If, in this case, the airbag is longitudinally tensed as the expansion of the airbag is completed, it cannot be arranged between the passenger""s head portion and the side window. On the contrary, the airbag pushes the head portion onto the side window.
The present invention contemplates to solve the above-specified problems. In short, the invention has an object to provide a head protecting airbag device which can arrange the expanded airbag smoothly between the passenger and the side window even if the passenger is close to the side window.
According to a first aspect of the present invention, there is provided a head protecting airbag device comprising an airbag folded and housed above the upper edge of a window inside of a vehicle and expanded while being extended to cover the inner side of the window when it admits an inflating gas. The airbag includes a body portion and an extension portion. The body portion covers the inner side of a side window positioned on the side face of the vehicle. The extension portion is arranged on at least the front side of the body portion, and extends on the inner side of the vehicle body generally perpendicularly to the side window. Moreover, the extension portion is formed into such a sheet shape having flexibility that it can be arranged in front of a passenger upon completion of the expansion of the airbag. Moreover, the body portion upon completion of the expansion fixes its upper edge on the body side while allowing the lower edge to move generally perpendicular to the side window upon completion of the expansion. The extension portion is fixed at its leading edge (the edge removed from the airbag body portion) on the vehicle body and is housed in a roof portion over the front side of the passenger such that it can protrude downward along with the body portion housed above the upper edge of the side window.
In the head protecting airbag device according to the first aspect of the invention, the body portion expands while extending downward from the upper edge of the side window positioned on the side face of the vehicle thereby to cover the inner side of the side window, when the airbag admits the inflating gas. Moreover, the extension portion is pulled by the body portion to protrude downward from the roof portion acting as the housing so that it is arranged in front of the passenger.
Even if the body portion of the airbag is arranged closer to the center of the cabin than the head of the passenger which is close to the side window at the beginning of completion of the expansion, the lower edge of the body portion can move generally at a right angle with respect to the side window. Therefore, the airbag having completed the expansion does not push the passenger forcibly onto the side window. If the vehicle makes a rollover, a transverse movement or a side collision, on the contrary, the passenger may move away from the side window and toward the center of the vehicle. If the airbag body portion then moves its lower edge inward and then returns it outward, it can enter into the space between the passenger and the side window. If the airbag body portion is then sandwiched between the passenger""s head portion and the side window, the head portion is properly restrained (or protected) by the airbag body portion.
Here, the extension portion""s leading edge apart from the body portion is fixed on the body side of the vehicle. However, the extension portion has flexibility. Therefore, the airbag body portion having completed its expansion can flex the extension portion to rock the lower edge like a free end. As a result, the body portion can smoothen the inward movement and the outward returning movement of the lower edge.
Upon completion of the expansion of the airbag, moreover, the airbag extension portion is arranged in front of the passenger. This extension portion is fixed at its leading end portion apart from the body portion on the vehicle body side and is connected at its root portion to the airbag body portion. Therefore, it is hard for the extension portion to move forward. As a result, the extension portion can restrain (or protect) the passenger""s head properly even if when it is on the inner side of the airbag body portion it moves forward.
In the head protecting airbag device according to the first aspect of the invention, therefore, even if the passenger is close to the side window, the airbag having expanded can be smoothly arranged between the passenger and the side window. Even if the passenger moves forward, moreover, the airbag can retrain the passenger smoothly.
In this head protecting airbag device of the first aspect, it is desired that the extension portion is formed to extend from the whole front vertical end of the body portion.
With this construction, the vicinity of the boundary between the extension portion and the body portion can be a wide area. Therefore, the extension portion can retain an area as wide as possible, thereby to improve its ability to retrain the passenger moving forward.
In this head protecting airbag device of the first aspect, moreover, the extension portion may be formed into a mesh shape for retaining a forward visibility.
With this construction, the extension portion is enabled to retain the forward visibility by the mesh shape even if the airbag completes its extension and expansion so that the extension portion is arranged in front of the passenger. Therefore, the passenger can grasp the surrounding situation easily. Here, this mesh-shaped structure may include a net shape or a lattice shape so that the extension portion can restrain the passenger moving forward and can retain the forward visibility.
According to a second aspect of the invention, there is provided a head protecting airbag device comprising an airbag folded and housed above the upper edge of a window inside of a vehicle and expanded while being extended to cover the inner side of the window when it admits an inflating gas. The airbag includes a body portion and an extension portion. The body portion covers the inner side of a side window positioned on the side face of the vehicle. The extension portion has flexibility and is arranged on at least one longitudinal end side of the body portion, and extends on the inner side generally perpendicular to the side window. Moreover, the extension portion is fixed at its leading end portion opposite from the airbag body portion. Moreover, the body portion is fixed at its upper edge upon completion of the expansion on the body side, and allows the lower edge upon completion of the expansion to move generally perpendicular to the side window. The body portion has a smaller length in the longitudinal direction at the time when it admits the inflating gas than that when it is in an extended but non-expanded state.
In the head protecting airbag device according to the second aspect of the invention, too, the body portion expands while extending downward from the upper edge of the side window positioned on the side face of the vehicle thereby to cover the inner side of the side window, when the airbag admits the inflating gas.
Even if the body portion of the airbag is arranged closer to the center of the cabin than the head of the passenger which is close to the side window at the beginning of completion of the expansion, the lower edge of the body portion can move generally at a right angle with respect to the side window. Therefore, the airbag having completed the expansion does not push the passenger forcibly onto the side window. If the vehicle makes a rollover, a transverse movement or a side collision, on the contrary, the passenger may move away from the side window inward of the vehicle. When the airbag body portion then moves its lower edge inward and then returns it outward, it can enter into the space between the passenger and the side window. If the airbag body portion is then sandwiched between the passenger""s head portion and the side window, the head portion is properly restrained (or protected) by the airbag body portion.
It is natural that the extension portion of the airbag retains the flexibility even if it is fixed at its leading end portion apart from the body portion on the body side of the vehicle. Therefore, the airbag body portion having completed its expansion can rock at its lower edge freely. As a result, the body portion can have smooth inward and outward movement of the lower edge.
Moreover, the airbag body portion expands to reduce its longitudinal length from that of the extended but non-expanded state. Moreover, the extension portion extending from at least one longitudinal end of the body portion is fixed at its leading end portion away from the body portion and on the vehicle body side. Therefore, the body portion and the extension portion upon completion of the expansion take such a shape similar to about one quarter of a cylinder so as to enclose the passenger. As a result, the airbag body portion arranged on the outer side of the passenger is difficult to move out of the vehicle even it is pushed by the passenger moving outward. Moreover, the passenger is properly restrained (or protected) on the inner side of the body portion or the extension portion of the airbag.
In the head protecting airbag device according to the second aspect of the invention, therefore, even if the passenger is close to the side window, the airbag having expanded can be smoothly arranged between the passenger and the side window. Even if the airbag is moved by the passenger moving outward, moreover, it can retrain the passenger properly.
In this head protecting airbag device of the second aspect, it is desired that extension portions of the airbag are arranged on the two longitudinal ends of the body portion.
With this construction, the body portion having completed its expansion is supported by the extension portions extending inward from the body portion""s two longitudinal ends. Thereby, it is harder for the body portion arranged on the outer side of the passenger to move outward even if it is pushed by the passenger moving outward. As a result, the body portion can improve its ability to retrain the passenger.
In the head protecting airbag device of the second aspect, moreover, it is desired that if the vehicle is constructed to have the side window on each of the two transverse sides, the airbag body portion is constructed to cover at least one of the transverse side windows of the vehicle.
In case the head protecting airbag device is mounted on a vehicle such as a single-cab vehicle having one row of seats, in which the side windows are arranged individually on the two transverse side faces, the airbag body portion may be arranged to cover at least one side window in the transverse direction of the single-cab vehicle.
In the head protecting airbag device of the second aspect, moreover, in case the airbag device is mounted on the vehicle which is constructed with a pillar portion extending generally vertically and with side windows in front of and at the back of the pillar portion, the airbag body portion may be constructed to cover the side windows and also the pillar portion. In this case, the airbag body portion is also restrained by the pillar portion from moving to the outside of the vehicle. Therefore, the it is harder for the airbag body portion to move to the outside of the vehicle even if it is pushed by the passenger moving outward.
In the head protecting airbag device of the second aspect, moreover, it is desired that the body portion includes a gas inflow portion for admitting the inflating gas, and that the gas inflow portion is constructed to have a plurality of expansion portions juxtaposed longitudinally for inflating in vertical rod shapes. With this construction, the body portion can easily have a great amount of shrinkage in the longitudinal direction when expanding. Moreover, the body portion can be better prevented from moving outward.
According to a third aspect of the invention, there is provided a head protecting airbag device comprising an airbag folded and housed above the upper edge of a window inside of a vehicle and expanded while being extended to cover the inner side of the window when it admits an inflating gas. The airbag includes a body portion and an extension portion. The body portion covers the inner side of a side window positioned on the side face of the vehicle. The extension portion is arranged on at least one longitudinal end of the body portion, and extends on the inner side generally perpendicular to the side window. Moreover, the extension portion has flexibility and is fixed at its leading end portion on the vehicle body. Moreover, the body portion is fixed at its upper edge to the vehicle body upon completion of the expansion, and allows the lower edge to then move generally perpendicular to the side window. When the airbag is housed, moreover, the body portion is housed such that it is covered with the roof head lining above the upper edge of the side window. On the other hand, the extension portion merged with the body portion is housed above the upper edge of a window adjoining the side window and covered with the roof head lining so that it can protrude downward.
In the head protecting airbag device according to the third aspect of the invention, too, the body portion expands while extending downward from the upper edge of the side window positioned on the side face of the vehicle thereby to cover the inner side of the side window, when the airbag admits the inflating gas.
Even if the body portion of the airbag is arranged closer to the center of the cabin than the head of the passenger which is close to the side window at the beginning of completion of the expansion, the lower edge of the body portion can move generally at a right angle with respect to the side window. Therefore, the airbag having completed the expansion does not push the passenger forcibly onto the side window. If the vehicle has a rollover, a transverse movement or a side collision, on the contrary, the passenger may move away from the side window to the center of the vehicle. When the airbag body portion then moves its lower edge inward and then returns outward, it can enter into the space between the passenger and the side window. If the airbag body portion is then sandwiched between the passenger""s head portion and the side window, the head portion is properly restrained (or protected) by the airbag body portion.
It is natural that the extension portion of the airbag retains flexibility even if it is fixed at its leading end portion on the body side of the vehicle. Therefore, the airbag body portion having completed its expansion can rock its lower edge freely so that the body portion lower edge can be smoothened in both its inward movement and outward movement.
At the time of housing the airbag, moreover, the body portion is so housed that it is covered with the roof head lining covering the inner side of the roof portion above the upper edge of the side window. On the other hand, the extension portion is housed and covered with the roof head lining so that it can protrude downward to merge into the body portion above the upper edge of a window adjoining the side window. Therefore, even if the airbag is housed on the vehicle, the appearance by the inner side of the vehicle becomes good.
In the head protecting airbag device according to the third aspect of the invention, therefore, even if the passenger is close to the side window, the airbag having extended and expanded can be smoothly arranged between the passenger and the side window. Moreover, the airbag can be mounted with an excellent appearance on the vehicle.
In this head protecting airbag device of the third aspect, the extension portions may be arranged on the two longitudinal ends of the body portion, the front extension portion housed above the upper edge of the front window and the back extension portion housed above the upper edge of the rear window.
With this construction, upon completion of the expansion of the airbag, the three windows, i.e., the front, side and back windows on the inner side can be covered with the single airbag. As a result, according to this airbag device, the performance of the airbag to restrain (or protect) the passenger inside of the vehicle can be better improved while keeping the excellent appearance of the inner side of the vehicle.
Moreover, the head protecting airbag device of the invention can also be constructed in the following manner. Specifically, the body portion of the airbag is housed by covering it with a door portion. Moreover, the body portion extends by pushing and opening the door portion when it admits the inflating gas. The body portion is provided with a gas inflow portion for admitting the inflating gas. This gas inflow portion is constructed to include a gas distributing passage portion extending longitudinally on the upper edge of the body portion to distribute the inflating gas inflow longitudinally in the body portion. Moreover, the body portion is so fixed on the vehicle body that the gas distributing passage portion protrudes below the door portion upon completion of the expansion.
With this construction, upon completion of the expansion of the airbag body portion, the vicinity of the gas distributing passage portion having expanded can protrude below the door portion. Therefore, the body portion can rock its lower end portion easily. As a result, the body portion can have inward and outward movements of the lower edge that are smoother.
On the other hand, the head protecting airbag device of the invention may also be constructed in the following manner. Specifically, the body portion includes a gas inflow portion for admitting the inflating gas. Moreover, the extension portion is constructed to be housed by being covered with a door portion that can be opened by pushing. Moreover, the extension portion includes a gas inflow portion at its upper end extended from the gas inflow portion of the body portion for pushing and opening the door portion when it admits the inflating gas.
With this construction, when the airbag expands, the gas inflow portion of the extension portion pushes and opens the door portion covering the extension portion easily. As a result, the extension portion smoothly protrudes downward even if it is bent inward at the body portion.